1. Field of the Invention
This invention generally relates to a stop mechanism of a model car. More particularly, the invention relates to a stop mechanism for use in a model car of a type in which driving force of a driving motor mounted to a car body is transmitted to driving rear wheels through an intermeshing gear to drive the model car, and the car body comes to a stop while undergoing spin-turn when rotation of the driving motor is stopped.
2. Description of the Related Art
Model cars operated through a remote control operation generally receive an operation signal transmitted from a transmitter by a receiver mounted to a car body and transmit the operation signal to a driving motor.
Therefore, the driving motor starts or stops rotating in accordance with instruction of the operation signal, and an operation state of the driving motor such as rotation and stopping is as such transmitted to driving wheels (mainly, rear wheels).
To improve a realistic feeling similar to that of actual cars, some of the model cars stop while a car body is under a spin-turn state (a transverse state relative to a driving direction) as is known in the art. In the model cars of this type, a stop rod is caused to protrude to a running road surface from the bottom surface of either the right or left side of the car body (from the left side in this explanation) simultaneously with the stop of rotation of the driving wheels. In this instance, the distal end of the stop rod is brought into touch with the road surface to generate frictional resistance on one of the sides of the car body. The model car stops while the car body turns to the left (that is, under the spin-turn state) owing to this frictional resistance.
To stop the car body under the spin-turn state, however, it is necessary to simultaneously push a stop button of a transmitter and a projection button of the stop rod. This operation of simultaneously pushing the two buttons is rather troublesome for an unskilled operator.
Further, to cause the stop rod to protrude from the bottom surf ace of the car body, a cam mechanism is necessary for moving the stop rod in a vertical direction. Nonetheless, when this cam mechanism is afresh assembled into the model car, the number of components increases and an overall construction gets more complicated.
It is an object of the invention to provide a model car that has an easy-to-operate transmitter for even an amateur, can reliably exhibit a spin-turn operation at the time of stop through a simple construction and can solve all the problems described above.
The invention of claim 1 for accomplishing the object described above provides a stop mechanism for use in a model car of a type in which driving force of a driving motor is transmitted to driving rear wheels through an intermeshing gear for running the model car, comprising a seesaw-shaped swing member mounted at a position of a car body deviated either to the right or left from a center line of the model car in a driving direction, and supported by an axle of the driving rear wheels in such a fashion as to be capable of swinging; a driving motor fitted to a rear side of the swing member; a stopper plate fitted to a front side of the swing member; a spring for always biasing the swing member in a direction in which the stopper plate of the swing member comes into touch with a road surface, interposed between the swing member and the car body; and an intermeshing gear arranged in such a fashion that when the driving motor is rotated for advance, reaction force transmitted from the driving rear wheels to the driving motor operates in a direction in which the stopper plate is separated from the road surface against the biasing force of the spring.
When the driving motor is rotated for advance according to the stop mechanism of the model car of the invention, its driving force is transmitted to the driving rear wheels through the intermeshing gear and the model car runs linearly straight.
In other words, when the driving motor is rotated for advance, the reaction force transmitted from the driving rear wheels to the driving motor operates in a direction in which the stopper plate is separated from the road surface against the biasing force of the spring. Since the swing member automatically inclines towards the rear side at this time, the stopper plate comes out of touch from the road surface and the right and left wheels of the driving rear wheels uniformly rotate and advance on the road surface.
When the driving motor stops rotating and advancing, inertia force acts on the model car. Therefore, the model car gradually decreases its speed and comes to halt. Since the reaction force from the driving rear wheels extinguishes at the same time, the reaction force resisting the biasing force of the spring no longer exists. Consequently, the swing member automatically inclines towards the front side and the stopper plate comes into touch with the road surface.
One of the right and left sides of the car body suddenly stops owing to the frictional resistance occurring at the distal end of the stopper plate. Because the driving rear wheels keeping touch with the road surface rotate due to inertia while decreasing the speed on the other side of the car body, the car body comes to halt under the spin-turn state to either the right side or the left side.
In the stop mechanism of a model car according to claim 1, the invention of claim 2 provides a stop mechanism wherein the intermeshing gear is arranged in such a fashion that a direction of reaction force transmitted from the driving rear wheels to the driving motor operates in the same direction as a direction in which the stopper plate is brought into touch with the road surface when the driving motor is rotated for backward movement.
In this case, the reaction force occurring when the backward turning force of the driving motor is transmitted to the driving rear wheels pushes the stopper plate to the road surface and the driving rear wheel in the proximity of the stopper plate is caused to float from the road surface. Consequently, when the driving motor is rotated for backward movement, continuous pivot rotation becomes possible with the stopper plate as the turning center. When the backward rotation is stopped, the model car as such comes to halt (the model car does not enter the spin-turn state because it is no longer running straight).